我们已经证明细菌膜蛋白 YeeE 介导硫代硫酸盐的吸收。硫代硫酸盐作为全球生物硫循环中的无机硫源用于细菌中的半胱氨酸合成。分辨率为 2.5 Å 的 YeeE 晶体结构揭示了一种前所未有的沙漏状结构，硫代硫酸盐位于带正电荷的外凹侧。YeeE由环和13个螺旋组成，其中包括9个跨膜α螺旋，其中大部分表现出分子内假222对称性。四个特征环被埋在 YeeE 的中心，并形成由九个螺旋包围的中心区域。额外的电子密度图和连续的分子动力学模拟表明硫代硫酸盐可以暂时保留在所提出的途径中的几个位置。

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We have demonstrated that a bacterial membrane protein, YeeE, mediates thiosulfate uptake. Thiosulfate is used for cysteine synthesis in bacteria as an inorganic sulfur source in the global biological sulfur cycle. The crystal structure of YeeE at 2.5-Å resolution reveals an unprecedented hourglass-like architecture with thiosulfate in the positively charged outer concave side. YeeE is composed of loops and 13 helices including 9 transmembrane α helices, most of which show an intramolecular pseudo 222 symmetry. Four characteristic loops are buried toward the center of YeeE and form its central region surrounded by the nine helices. Additional electron density maps and successive molecular dynamics simulations imply that thiosulfate can remain temporally at several positions in the proposed pathway. We propose a plausible mechanism of thiosulfate uptake via three important conserved cysteine residues of the loops along the pathway.